from my point of view, it's really down to aesthetics and weight. the "Line" is sleeker looking, but noticeably heavier. the "Wave" has a retro sort of look, but it's grown on me since i first saw this bike last year. also, it looks awesome in black...

now that i've had time to think about it, i think you should definitely get the Wave. it folds better. it looks cooler, it's lighter, AND it seems to inspire laughter and a sense of vandalism in the user:

now that i've had time to think about it, i think you should definitely get the Wave. it folds better. it looks cooler, it's lighter, AND it seems to inspire laughter and a sense of vandalism in the user:

I like the style of the Wave better. Neither of them would get my nod if I was deciding on a new folding bike, but if these were the only two choices, I'd go with with the more interesting design, visually.